Luwan District For 50 Years Measles Epidemic Situation And Control Strategy,

This research selects Luwan District as the pilot. It describes the epidemiologic features of measles and the effects of immunization in Luwan District of Shanghai from 1956 to 2006, by using the methods of retrospective collection and Serological survey, studies the developing trend, transition routes, epidemiologic features of measles, investigates and analyses measles immunization levels of general groups, pregnant women and newborn babies by measuring measles IgG antibody. The objective of this research is to comprehensively analyze and judge the spreading state of measles in Luwan, and to explore the effective strategies to prevent and control the spread of measles, especially the policy of decreasing the incidence of measles of babies. The research is expected to enlighten future prevention of measles. This research is composed of four parts.Part One: Analysis of the 50 years' epidemiologic features of measles in Luwan District of Shanghai. Analysis the incidence and fatality data of measles from 1956 to 2006 has been made. There are three epidemic measles and the total cases are 114685 in 50 years in Luwan District. The highest reported incidence reached 4317.4/100000 in 1958 and the highest reported mortality rate reached 22.70/100000 in 1957. Before vaccination was carried out, the mean incidence was over 1000/100000. During the immunization period, incidence has been descending remarkably year after year, mortality rate remained under 1/100000.Incidence has been controlled under 4/100000, and mortality rate under 0.05/100000, fatality rate under 0.2% in 80s. After 1986, there is no one died from measles. From 90s till now, incidence has been controlled under 1/100000.In 2005,measles spreades, incidence is 2.50/100000, which is the highest in recent twenty years. The season peak shifts from winter to spring and appears from March to May. In each period, incidences of infants and children are highest and descend most sharply and incidences of adults descend little. But the cases of adults account for 70% of the total cases. The difference between sex-specific incidence rates is small and the ratio is 1.18: 1. The cases of workers and staffers are more than that of other professions. Adults have became main sufferers, and that indicates the epidemiologic feature of measles in Luwan District nowadays. This is a problem which should be solved urgently in the process of eliminating measles. The programme on immunization should be expanded for improving the immunization level of adult.Part Two: Analysis of the effects of MV immunization in Luwan District of Shanghai in 50 years. Analysis of Serological surveillance datum is made. Measles Vaccine begins used in 1965 in Luwan District, MV inoculation rate has raised over 99% since 1994. Surveillance of MV immunization begins in 1986, seroconversion rate and 4-times protection rate reach over 97% and 97% respectively. The positive rate remaines over 90% in 6 years after vaccination. Measuring antibody level in general groups has been carried out since 1987. The positive rate in each year remaines over 98% and this showes that the immunization level in Luwan District is high.Incidence is inversely correlated to immunization rate, Incidence of measles is now at the lowest level which shows the great effects of immunization and good inoculation job in Luwan District.Part Three: Study of the immunization level of general groups in Luwan District. By applying Serological survey to test measles IgG antibody of general groups, the study shows that the total positive rate of IgG antibody was 81.21%, the immunization level of 6 to 7-month babies is low, the positive rates in 15～49-age groups are under 90%, they are susceptibles of measles. The question of insufficient matriclinous antibody should arouse general concern, In order to raise the matriclinous antibody level and to decrease baby's incidence of measles, revaccination in unmarried women of child-bearing age is recommended. The programme on immunization should be expanded for improving the immunization level of adult and protecting susceptible people.Part Four: Study on measles immunization level of mother and newborn babies. By applying seroepidemiology to measure measles IgG antibody of mother and newborn babies, the study shows the positive rate of IgG of 71 pregnant women is 84.51% and that of newborn babies is 73.24%. The positive rate of IgG of pregnant women with Shanghai household register is 84.38% and that of pregnant women without Shanghai household register is 84.62%. 69.01% of all the 71 women have positive IgG antibody whth their babies' IgG antibody positive as well. 11.27% of all the 71 women have negative IgG antibody whth their babies' IgG antibody negative as well. The measles antibody level of pregnant women is highly correlated to that of their newborn babies. In order to raise the matriclinous antibody level and to decrease baby's incidence of measles ,revaccination in unmarried women of child-bearing age is recommended.